Chief Cabinet Secretary Yukio Edano yesterday ruled out the possibility that the two undamaged reactors at Tokyo Electric Power Co.'s six-unit Dai-Ichi plant would be salvaged. Units 1 through 4 suffered from explosions, presumed meltdowns and corrosion from seawater sprayed on radioactive fuel rods after a March 11 earthquake and tsunami cut power to reactor cooling systems.

Workers have averted the threat of a total meltdown by injecting water into the damaged reactors for the past two weeks. The complex's six units are connected with the power grid and two are using temporary motor-driven pumps. Work to repair the plant's monitoring and cooling systems has been hampered by discoveries of hazardous radioactive water.

High Radiation Levels Found in Seawater Near Japanese Nuclear Plant (New York Times): TOKYO -- Seawater near the crippled Fukushima Daiichi nuclear power plant shows significantly higher levels of radioactive iodine than in recent days, Japan's nuclear safety agency reported Wednesday, and the operator of the plant publicly acknowledged for the first time that at least four of the six reactors at the multibillion-dollar complex would have to be scrapped.

Hidehiko Nishiyama, deputy director general of the Nuclear and Industrial Safety Agency, said that seawater collected about 300 yards from the Fukushima Daiichi station was found to contain iodine 131 at 3,355 times the safety standard, the highest levels reported so far. On Sunday, a test a mile north showed 1,150 times the maximum level, and a test the day before showed 1,250 times the limit in seawater taken from a monitoring station at the plant.

Workers have been dousing the reactor fuel rods with emergency infusions of seawater and now from freshwater sources, but the "feed and bleed" method of cooling the reactors to prevent full meltdown has released harmful amounts of radioactive steam into the atmosphere and set off leaks of highly contaminated water.

Tests on seawater near the nuclear power plant showed that levels of radioactive iodine reached 3,355 times the legal limit on Monday, one of several peaks in recent days that have fallen rapidly as radioactive substances decayed and were steadily diluted and dispersed by ocean currents.

Officials are watching levels of iodine-131 in seawater because although it has a half-life of eight days, meaning it is half as radioactive after that time, the substance builds up in seaweed, a common food in the Japanese diet. If consumed, radioactive iodine collects in the thyroid and can cause cancer.

Japan crisis will redefine the future for nuclear power (The National): The Fukushima disaster is still unfolding, but it now appears the crisis could end up rivalling Chernobyl as a category 7, the highest degree. But even before the scientific facts are known, lessons can already be drawn from the accident in the context of the current political upheaval in the Middle East.

The end of nuclear power is nowhere in sight; nuclear power is here to stay. There are more than 400 operating reactors in the world, each with a planned operating timespan of at least 40 years. No responsible government will want to squander that investment.

Those who refer to a "pause" do it largely to appease worried citizens. Even countries which claim that they will now prepare their exit from the nuclear era will continue to rely on nuclear reactors for several decades.

Nuclear plant setbacks mount in Japan (The Associated Press): TOKYO -- Setbacks mounted Wednesday in the crisis over Japan's tsunami-damaged nuclear facility, with nearby seawater testing at its highest radiation levels yet and the president of the plant operator checking into a hospital with hypertension.

Nearly three weeks after a March 11 tsunami engulfed the Fukushima Dai-ichi plant, knocking out power to the cooling system that keeps nuclear fuel rods from overheating, Tokyo Electric Power Co. is still struggling to bring the facility in northeastern Japan under control.

Radiation leaking from the plant has seeped into the soil and seawater nearby and made its way into produce, raw milk and even tap water as far as Tokyo, 140 miles (220 kilometers) to the south.

German Chancellor Angela Merkel has offered Japanese Prime Minister Naoto Kan "to make available special radio-controlled equipment from Germany that can be used for cleanup and repairs of reactors," her spokesman Steffen Seibert said in a statement.

Japan was considering the offer, the statement said on Wednesday. A government spokesman could not immediately verify which devices could be sent.

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